1. Field of the Invention
The present invention relates to enclosures for the boxes of pick-up trucks and more specifically relates to such enclosures that include a roof that can be opened.
2. Description of the Prior Art
A variety of devices are known in the art for covering the top of a pick-up box or for providing a container employable with a pick-up box and having a roof that can be opened. Such constructions are employed so that the pick-up can be utilized in conventional fashion for hauling large objects without removing the box cover or the container from the pick-up. This is particularly true when the container on the pick-up box is relatively large such as those commonly referred to in the art as a "topper." Usually toppers are relatively heavy and are awkward for removing or installing. Consequently, it is highly desirable to have an adaptable construction for a topper so that the roof will open so the pick-up box can be employed for normal usage.
A known structure for enclosing pick-up boxes is disclosed in U.S. Pat. No. 3,995,890 issued to Fletcher. The Fletcher structure includes a roof formed in two sections that are pivotally secured to the sidewalls by elongated lever arms that are associated with hydraulic rams for opening and closing the roof sections. In U.S. Pat. No. 3,858,744 issued to Garvert, a cover structure is disclosed that includes a pair of panels hinged to sidewall portions of a pick-up box. An associated brace structure is utilized for holding the cover panels in a vertical position, and a strut and a second brace for holding the cover in an outer horizontal position to thus open the box. Various other types of pick-up box enclosures are disclosed in U.S. Pat. Nos. 4,284,303, 4,832,394, and 3,861,737.
Although the above prior art structures provide cover arrangements for pick-up boxes, they are all deficient in the aspect that they do not provide a cover of relatively simplistic construction and operability to permit the cover portions to be readily moved from a closed position to an opened position secured against the sidewalls of the pick-up box.